Diazotype material



United States Patent K Int. Cl. G03c 1/54; C07c 113/04 US. Cl. 96-91 13Claims ABSTRACT OF THE DISCLOSURE Diazotype material of improvedstability and light sensitivity includes a 3-quaternary ammonium-alkoxysubstituted p-phenylene diamine derived diazonium compound.

The present invention relates to a diazotype material and moreparticularly relates to improved photosensitive diazo components usefulin diazotype reproduction material.

In copying papers and other diazotype materials that have beensensitized with diazo compounds, the den'vatives of unilaterallydiazotized p-phenylene diamine have been used as the photosensitivecomponents. These diazonium compounds have a tertiary amino group ofbasic character and they have been used successfullyfor both the dryprocess and the semi-wet process.

For the dry process the diazo compounds which are most suitable arethose containing lower alkyl groups attached to the basic nitrogen atom,while for the semi-wet process the best ones are those in which thebasic nitrogen atom is attached to higher hydrocarbon radicals.

The substituents on the basic nitrogen atom affect not only couplingspeed, but they also affect the light-sensitivity and keeping qualitiesof the diazo compounds and the light-sensitive layers preparedtherewith.

In considerable measure the properties of the p-amino benzene diazocompounds depend also on substituents attached to the phenylene ring. asubstituent such as a methyl, methoxy, or carboxyl group in a positionortho to the diazonium group, brings about a considerable improvement instability and at the same time a color shift toward blue.Light-sensitivity is, however, lowered by these substituents. Thepresence of an alkoxy group in a position meta to the diazonium groupmakes the diazo compound considerably more light-sensitive in relationto the unsubstituted compound, but the keeping qualities become pooreras a result. Despite their poor stability, this type of diazo compoundis nevertheless important because of its high light-sensitivity and itfinds practical use in cases where copies have to be prepared as quicklyas possible.

It has been found that the stability of this general type ofmeta-substituted diazonium compound can be improved without loss oflight-sensitivity through the use of hetero-atom substituents in thealkoxy group in the position meta to the diazonium group. Some usefulimprovements in such diazonium compounds have been disclosed in relatedcopending US. patent applications owned by the assignee of the presentinvention. U.S. application Ser. No. 311,220, filed Sept. 24, 1963, nowUS. Patent No. 3,272,630 describes a group of alkoxy-aryloxyand tertiaryamino-substituted 3-alkoxy diazonium compounds. Application Ser. No.414,878, filed Nov. 30, 1964, now U.S. Patent No. 3,281,246 describes agroup of alkylmercaptoand amino-substituted 3-alkoxy diazoniumcompounds. Application Ser. No. 425,921, filed Jan. 15, 1965, describesa group of alkoxy-, alkylmercaptoand amino substituted 3 hydroxya-lkoxydiazonium com- 3,459,551 Patented Aug. 5, 1969 pounds. Application Ser.No. 547,738 filed May 5, 1966, describes a group of alkoxy-substituted3-alkoxy-4-hydroxyalkylamino-diazonium compounds.

Now, according to the present invention, there is provided diazo-typematerial having improved stability and light-sensitivity comprisingsubstituted p-aminobenzene diazonium compounds with meta-substituentsincluding a quarternary amino group as part of the hetero-atom. Thelight-sensitive diazonium compounds of the present invention have thegeneral formula:

wherein R stands for 'an alkyl group with at the most four carbon atoms,

R stands for an alkyl group with at the most four carbon atoms or anaralkyl group with at the most ten carbon atoms, or

R and R together with the nitrogen atom N to which they are attached,form a heterocyclic group which may bear one or several substituents,

R stands for an alkylene radical which contains at least 2 C-atoms andmay also be substituted,

R and R stand for alkyl or hydroxyalkyl, or

R and R together with the nitrogen atom to which they are attached, forman unsubstituted or substituted heterocyclic radical,

R stands for alkyl or aralkyl,

X stands for a hydrogen or halogen atom or an alkyl or alkoxy group,

Y and Y each stand for the anion of an acid.

The p-aminobenzenediazonium salts according to the above mentionedgeneral formula exhibit high light-sensitivity and excellent stability.Their substantivity is bet ter than that of the p-aminobenzenediazocompounds which characterize the reproduction material described in theabove-mentioned copending applications. Diazotype material prepared withthese diazonium compounds exhibit improved properties in respect ofshelf life and advantages which show themselves during its processingand in the copies prepared from it.

Diazotype materials comprising the present diazonium compounds can beprepared in the usual manner and can be used to advantage in both thedry or semi-wet diazotype processes. Depending upon the azo couplercomponent selected, images of deep color can be prepared with greatspeed.

The p-aminobenzenediazo compounds corresponding to the general formulastated above have not yet been described in the literature. They areobtained according to processes which are described in the literatureand in particular in the mentioned co-pending applications. Thep-tertiary-aminonitrobenzenes with a tertiary amino group in the ethergroup in the meta-position which are mentioned in these applications canbe converted into the quaternary form by conventional methods with e.g.alkyl halides or aralkyl-halides or dialkylsulphates. Conversion ofthese quaternised compounds into diazo compounds is effected withoutdifficulty.

- The separation of the diazo compound is eifected in the form of itsmetal halide double salts or in other manner known in the art.

In the table are set forth the formulae of some diazo compounds by whichthe reproduction material according to the invention is characterized.In the examples, typical preparation of some of these compounds andpreparation, in the usual manner, of diazotype materials employing thesame are described. The weight and volume units in the examples may benominally considered as milliliters and grams.

A photocopying base paper of the kind commonly used in diazotypeprocesses, one side of which is provided with a precoat consisting ofcolloidal silicic acid and polyvinyl acetate, is coated on the precoatedsurface with a solution which contains in parts by volume of water Partsby weight Citric acid 3.5 Boric acid 3.5 Thiourea 5.03.5-dihydroxy-4-bromobenzoic acid amide 1.2

Diazo compound fromtriethylbeta-(5-amino-2-pyrrolidino-phenoxyethyl)-ammonium chloride inthe form of the zinc chloride double salt (Formula 1) 2.4

parts by weight of 2-chloro-5-nitrophenol are dissolved in 400 parts byvolume of methylglycol and 220 parts by volume of ethylenebromide andheated to the boil, with stirring. Under reflux, a solution of 24 partsby weight of sodium hydroxide in 250 parts by volume of water is addeddropwise to the methylalcoholic solution in 3 hours. After furtherstirring for two hours under reflux the reaction mixture is filteredwith suction while hot, the filtrate concentrated to dryness in vacuo,and the residue treated with water, filtered with suction and dried.Yield: 165 parts by weight with a melting point of 71- 75 C.

305 parts by weight of 2-ch1oro-5-nitrophenyl-beta bromoethylether with385 parts by weight of anhydrous diethylamine and 60 parts by volume ofwater are heated to the boil, with stirring. After boiling for two hoursthe reaction mixture is poured into ice water, filtered with suction andwashed thoroughly with ice water. While the 395 parts by weight ofreaction product which are obtained are still moist, there are pouredover it 450 parts by volume of pyrrolidine and 30 parts by volume ofwater and the mixture is heated to the boil, with stirring. After themixture has been stirred for about three hours under reflux, 180 partsby volume of pyrrolidine are distilled off. The residue is poured intothe ice water, filtered with suction and washed thoroughly with water.Yield of 5 nitro 2 pyrrolidinophenyl beta diethylaminoethylether: 325parts by weight, with a melting point of 39 C. After recrystallizationfrom petroleum ether the melting point of 42 C. is obtained.

160 parts by weight of S-nitro-2-pyrrolidinophenyl-betadiethylaminoetherare dissolved in 100 parts by volume of acetone. This solution is heatedto the boil, with stirring, and there are added to it dropwise 75 partsby volume of ethyl iodide. After stirring for a further hour underreflux the reaction mixture is cooled, filtered with suction, digestedwith acetone and dried. Yield: 95 g. with a melting point of 197 C.

30 parts by Weight of the triethyl-beta-(S-nitro-Z-pyrrolidino-phenoxyethyl)-ammonium iodide thus prepared are hydrogenatedwith hydrogen in 200 parts by volume of methanol in the presence ofactive nickel catalyst. The amino compound formed, after filtering offthe catalyst and evaporation of the solvent, is dissolved, withoutpurification, in 80 parts by volume of water and 20 parts by volume ofhydrochloric acid and diazotised at 0-10 C. with 33 parts by volume of 2N sodium nitrite solution. After dilution of the diazotising mixturewith 100 parts by volume of water the mixture is filtered over carbon.An aqueous solution of 15 parts by weight of zinc chloride is added toit and salting out is efiected with sodium chloride. Yield: 11 parts byweight of the compound of Formula I after dissolving in water andprecipitating by adding sodium chloride solution.

Example 2 A photocopying base paper of the kind commonly used indiazotype processes, one side of which is provided with a precoatconsisting of colloidal silicic acid and polyvinyl acetate, is coated onthe precoated surface with a solution which contains in 100 parts byvolume of water Parts by weight Citric acid 4.0 Thiourea 5.0 Aluminumsulphate 3.0 Sodium 1,3,6-naphthalenetrisulphonate 3.5

and then dried.

The reproduction paper has very good shelf life.

The resulting reproduction paper is imagewise exposed in the normalmanner under a transparent original and then developed with ammoniavapour. Blue images on a White back ground are obtained.

The diazo compound used (that of Formula III) is prepared in manneranalogous to that stated for the diazo compound described in Example 1.However, in this case the 2-chloro-5-nitrophenol is reacted withepichlorohydrin instead of with ethylene bromide.

The foregoing examples have been presented for the purpose ofillustration and should not be taken to limit the invention. It will beapparent that the present invention is capable of numerous variationswhich will be included within the scope of the appended claims.

What is claimed is:

1. A diazotype reproduction material comprising a support and aphotosensitive composition coated thereon, said composition comprising aphotosensitive diazonium compound having the general formula:

wherein:

(a) R is an alkylene group having two to four carbon atoms orbeta-hydroxypropylene;

(b) R is an alkyl group having one to four carbon atoms, and R is analkyl having one to four carbon atoms or aralkyl, or R and R togetherwith the nitrogen, form a pyrrolidine, piperidino, or morpholino p;

(c) R; is an alkyl or hydroxyalkyl group and R is an alkyl orhydroxyalkyl group, or R and R together with the nitrogen, form anunsubstituted or substituted 5- or 6-membered heterocyclic group;

(d) R is an alkyl having one to four carbon atoms, or

benzyl;

(e) X is a hydrogen or halogen atom, or an alkyl or alkoxy group; and

(f) Y and Y are each an anion of an acid.

2. Material according to claim 1 wherein said diazoniurn compound is thezinc chloride double salt of 3,4- pyrroldino-benzene diazonium chloride.

3. Material according to claim 1 wherein said diazonium compound is thezinc chloride double salt of 3,4- pyrrolidino-benzene diazoniumchloride.

4. Material according to claim 1 wherein said diazonium compound is thezinc chloride double salt of 3,4- pyrrolidino-benzene diazoniumchloride.

5. Material according to claim 1 wherein said diazonium compound is thecadmium chloride double salt of 1-ethoxy-4-morpholino-5benzene diazoniumchloride.

6. Material according to claim 1 wherein said diazonium compound is the3,4-morpholino-benzene diazonium borofluoride.

7. Material according to claim 1 wherein said diazonium compound is theZinc chloride double salt of 3,4- pyrrolidino-benzene diazoniumchloride.

8. Material according to claim 1 wherein said diazonium compound is thezinc chloride double salt of 3,4 (N-ethyl-N-butyl)-amino-benzenediazonium chloride.

9. Material according to claim 1 wherein said diazonium compound is thecadmium chloride double salt of 3,4- pyrrolidino-benzene diazoniumchloride.

10. Material according to claim 1 wherein said diazonium compound is thezinc chloride double salt of 3,4- piperidino-benzene diazonium chloride.

11. Material according to claim 1 wherein said diazonium compound is thecadmium chloride double salt of 2- methyl-4-morpholino-5-benzenediazonium chloride.

12. Material according to claim 1 wherein said diazonium compound is thezinc chloride double salt of 2-chloro- 3,459,551 7 84-(N-methyl-N-benzyl) amino 5 benzene diazonium 3,281,246 10/1966 Rauhutet a1 96-- 91 chloride. 3,343,960 9/1967 Sus 9691 13. Material accordingto claim 1 wherein said diazonium compound is the zinc chloride doublesalt of 3,4- NORMAN G. TORCHIN, Primary EXamiHBl diethylamino-benzenediazoniurn chloride. 5 BOWERS, Assistant Examiner References C1ted USICL- XIR. UNITED STATES PATENTS 260141, 142, 567 3,272,630 9/1966 Rauhutet a1 96-91 XR

